1. Field
The present disclosure relates to a control device, an internal combustion engine system, and a method.
2. Description of the Related Art
Japanese Unexamined Patent Application Publication No. 2007-23837 discloses a control device for internal combustion engine which includes a valve actuation variable mechanism and a supercharger with electric motor. When an electronic motor is actuated to perform supercharging, differential pressure between intake pressure and exhaust pressure (=intake pressure−exhaust pressure) is increased. Therefore, the amounts of fuel and intake air which flow into a combustion chamber and are directly exhausted to an exhaust passage without contributing to combustion (passing-through amount) tend to increase. In order to reduce this passing-through amount, the above-mentioned control device performs control for shortening an overlap period, in which a valve opening period of an intake valve and a valve opening period of an exhaust valve are overlapped with each other, in actuation time of an electric motor (when driving auxiliary of a supercharger is performed) so as to be shorter than that in non-actuation time of the electric motor. Accordingly, excessive increase of the passing-through amount is prevented.